For each regular language \(\mathcal {L}\) , there exists a unique (up to a re-labelling isomorphism) minimal recognizer DFA \(\mathcal {D}\)  [1]}.
Given the minimal DFA \(\mathcal {D}\)  of the ground-truth grammar and the minimal DFA \(\mathcal {D}^{\prime }\)  of the induced grammar, we canonically re-label their states and follow the algorithm of [2]} to test whether \(\mathcal {D},\mathcal {D}^{\prime }\)  are isomorphic.
Isomorphism of \(\mathcal {D},\mathcal {D}^{\prime }\)  means that \(\mathcal {G},\mathcal {G}^{\prime }\)  are fully equivalent, implying that our model has achieved the maximum recall and precision and that we do not need to evaluate further.
